Moral realism

Moral realism is the view that moral claims can be true or false independently of individual attitudes. It treats at least some moral truths as objective rather than merely expressions of preference.

Moral judgment: An evaluation that something is morally right, wrong, good, or bad. Realism concerns whether such evaluations can be true independently of anyone's attitudes.
Moral anti-realism: The family of views denying that morality includes objective facts or truths independent of attitudes. It directly rejects realism's central commitment to attitude-independent moral truth.
Naturalistic moral realism: The view that moral facts are objective and reducible to, or grounded in, natural facts. It explains realist truth by identifying moral properties with natural properties.
G. E. Moore: The British philosopher whose Principia Ethica defended non-natural moral properties and criticized naturalistic definitions of goodness. Moore's open-question argument became a landmark defense of non-naturalist realism.
Moral disagreement: Persistent conflict among people or societies about moral judgments and principles. Widespread disagreement is often raised as evidence against objective moral truth.
Moral truth: Truth about what is morally right, wrong, good, or valuable. Realism holds that at least some moral claims state moral truths.
Moral subjectivism: The view that moral truths depend on the attitudes or responses of individuals. It makes moral truth dependent on attitudes that realism treats as non-determinative.
Non-naturalism: The view that moral properties are objective but cannot be reduced to natural properties. It preserves objective moral facts while denying that natural science fully captures them.
W. D. Ross: The British philosopher who argued that several irreducible prima facie duties are self-evident. Ross offered a realist account of moral duties that resists reduction to one principle.
Argument from queerness: Mackie's argument that objective values would be metaphysically and epistemically unlike anything else. It presses realists to explain what moral facts are and how they could be known.

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